采用水文变异法(RVA)对梯级水库运行引发的在时间和空间上水文条件的累积变异特性进行定量化研究.研究结果显示:在时间累积层面,有龙梯级水库运行较无龙梯级水库运行指标改变更为强烈,其中56%的指标加剧恶化,且主要集中在极值指标与高流量参数方面;而在空间累积层面,沿梯级水库累积方向,改变程度整体呈减小趋势,指标体系中3,12 m平均流量,最小3,30,90 d流量,最大1,7 d流量,基流以及逆转次数等指标发生严重变异,且对水库空间累积不敏感.下游综合利用水库对上游水库产生的变异状态有修复作用,即趋于有利;而以发电为主的水库对下游水文条件的影响表现为有限趋弊.
The range of variability approach(RVA) was used to study the quantitative cumulative variation of hydrological conditions in time and space caused by the operation of cascade reservoirs.It was shown that from the time aspect,the variation of hydrological indices with the operation of Longyangxia Reservoir was severer than that without the operation of it and 56% of them were worse,including parameters of extreme values and high flow discharges.From the space aspect,the overall level of the variation of the hydrological indices had a decreasing tendency along the accumulative direction of the cascade reservoirs.However,some indices of the average flows in March and December,the minimum flows in 3,30 and 90 days,the maximum flows in 1 and 7 days,the basic flows and the numbers of hydrological reversals had serious variation and were not sensitive to the space cumulative change of the reservoirs.Through a comparative analysis,conclusion are drawn that the downstream reservoirs can restore the impact from the upstream ones,but the reservoir objected to generate power will make the hydrological conditions be worse at a limited degree.